Self-contained refrigerating freight car unit



H. W. KLEIST April 21, 1953 SELF-CONTAINED REFRIGERATING FREIGHT CAR UNIT original Filed June 28, 1948 5 Sheets-Sheet l H. W. KLEIST April 21, 1953 SELF-CONTAINEDI REFRIGERATING FREIGHT CAR UNIT Original Filed June 28, 1948 5 Sheets-Sheet 2 April 21, 195s H. w.v KLElsT SELF-CONTAINED REFRIGERATING FREIGHT CAR UNIT 5 Sheets-Sheet T5 Original Filed June 28, 1948 70 109 lll' ITN/e 72250 7" Herman 777K ./Zorzqgt Patented Apr. 21, 1953 UNITED STATES PATENT OFFICE SELF-CONTAINED REFRIGERATING FREIGHT CAR UNIT Herman W. Kleist, Chicago, Ill., assignor to Dole Refrigerating Company, Chicago, Ill., a corporation of Illinois 8 Claims.

My invention relates to an improvement in cars, trucks and the like, and has for one purpose the provision of a refrigerating system for insulated freight cars.

Another purpose is to provide a hold-over system for freight cars in which, while the freight car carries its own power source, and refrigeration cycling equipment, it is necessary to operate it only at relatively wide intervals.

Another purpose is to provide such a system in which no operation of the cycling mechanism is necessary during a normal run or trip of a particular car, whereby the car may be loaded, transported to its destination, and unloaded, during the interval between successive actuation of the refrigerant cycling mechanism.

Another purpose is to provide an improved car structure in which a cycling mechanism is insulated from the interior of the car.

Another purpose is to provide a refrigerating system in which a group of refrigerating plates or units are used to heat an interior space and in which one or more of the units can be cut out at the desire of the user.

Another purpose is to provide such an arrangement in which some of the plates or evaporators are automatically out out, for example, in response to changes in temperature within th space to be refrigerated.

Other purposes will appear :from time to time in the course of the specification and claims.

I illustrate the invention more or less diagrammatically in the accompanying drawings, where- Figure l is a vertical longitudinal section through a typical freight car;

Figure 2 is a section on an enlarged scale on the line 2-2 of Figure 1;

Figure 3 is a section illustrating the additional employment of refrigerating elements along the side of the car;

Figure 4 is a partial vertical longitudinal section illustrating the use of a car end cooling member;

Figure 5 is a section with parts broken away illustrating a typical cooling member;

Figure 6 is a section on an enlarged scale along the line 6-5 of Figure 5;

Figure 7 is a wiring diagram illustrating the controls of the system; and

Figure S is a diagrammatic illustration of a variant control arrangement.

Lilie parts are indicated by like symbols throughout the speciiication and drawings.

The present application is a division of my vcopending application Serial No. 35,545, led June 28, 1948, issued on December 19, 1950, as Patent No. 2,534,273.

Referring to the drawings, A generally indicates a refrigerated freight car which includes insulated ends l, 2 and insulating roof structure 3, an insulating iioor structure 4, and insulated side wall structures 5 and 5a.. It will be understood that any suitable insulated structure may be employed, the details of car insulation not, of themselves, forming a part of the present invention.

Referring to Figure 1, I flnd it advantageous to employ a separate cabinet or house, insulated from the interior of the car. Whereas such a house or compartment may be formed in a variety of ways, I illustrate as an example, a compartment which includes an insulated bottom Wall E and an insulated side wall l. The

' compartment may extend entirely across the freight car or it may be of less width than the interior of the freight car, depending upon the desire of the designer. With reference to Figure 1, the space within the compartment is insulated by the walls 6 and l from the interior of the freight car, but is preferably otherwise bounded by non-insulated wall areas. I illustrate for example, an opening 8 in the end wall of the freight car which is closed by a louver member 9 which permits the entry or circulation of air. A similar louver member lll is shown in one of the car side walls. The roof structure is provided with a non-insulated portion indicated at Il.

Within the housing thus formed I illustrate a compressor l2 which may be driven by any suitable motor I 3. I 1i is a return or suction duct extending to the compressor. The compressor delivers compressed refrigerant through the duct I5 to any suitable condenser I6 from which condensed refrigerant may flow to a receiver Il for delivery through the pressure duct i8. It will be understood that any suitable means may be employed for circulating air or a suitable cooling medium about the condenser i6. Any suitable means may be employed for causing a pressure drop whereby the volatile refrigerant which flows through the duct i3 through the below described cold plates or evaporators may have its pressure reduced to the desired degree.

I illustrate diagrammatically any suitable pressure reduction valve or assembly I9. A common pressure reduction valve may be employed for groups of evaporators or for the entire evaporator system. An important feature of my invention, and one not shown in detail in Fig. 1,

is the provision of automatic and preferably heat responsive means for varying the number of plates to which the volatile refrigerant flows. Because of lack of space, this feature is not shown in Fig. 1 but is indicated diagrammatically in Fig. 8, it being applicants desire that Fig. l be read as if the material in Fig. 8 were included in it. It will be understood that when the motor I3 is driving the compressor I2, the gaseous refrigerant from the return duct or pipe I4 is compressed and condensed and delivered back toward the evaporators or cooling elements through the duct I8.

Whereas I may use a variety of evaporating elements, I prefer to employ hold-over vacuum plates in which an evaporator coil is surrounded by a eutectic and is held in adequate heat conducted relation with the preferably plane walls of a plate structure. Referring for example to Figures 5 and 6, I illustrate a plate for plane parallel walls 25 and 26 which with circumferential side walls Z'I form a closed container. Within this container is formed or bent any suitable evaporator coil 28. The evaporator coil receives a volatile refrigerant, at a reduced pressure from the supply pipe I8 through the pressure reduction structure I9. The individual members may be arranged in any suitable arrangement or circuit but for convenience I illustrate them herein arranged in series and connected by connecting ducts 30, the whole series eventually returning the evaporated refrigerant to and through the return pipe or duct I4. I find it advisable partially to exhaust the air within the individual unit. I may for example, employ an aperture 3| which is closed by any suitable fitting 32 which is sealed after the eutectic has been added and the air has been partially exhausted. Preferably I leave an empty space of l0 percent or less of the capacity of the interior of the plate, rather than filling the plates completely with the eutectic,

With reference, for example, to Figure 2-, I illustrate the individual vacuum plates, which I indicate as B in a pair of rows which may extend substantially from end to end of the car. The individual plates .may be supported by their edge flanges or extensions 35 upon any suitable brackets 36. Preferably the parts are so arranged that the plates may readily be removed from the brackets. For example, in Figure 2, the plates are not actually secured to the brackets but merely rest upon them. As an inner edge of a plate is raised to the inner surface of the roof, the outer edge is then freed from its supporting brackets 36 and the plate may be removed. However, if desired to prevent an unintended movement of the plates, they may be bolted or otherwise removably secured to the brackets.

Beneath each row of brackets, I illustrate drip receiving pans 38 mounted in any suitable brackets 39 and provided with liquid drip outlets 40 normally closed and controlled by any suitable valve knobs or handles 4 I.

In the form of Figure 1, I illustrate the plates as arranged only along the roof of the car. It will be understood that the brackets are formed and disposed to permit free circulation of air between the pans 38 and the roof and about the cold plates B.

With reference to Figure 3 I may find it advantageous to add a series of cold plates C along the sides of the car. These may be supported at their upper and lower ends as by brackets 45. Any suitable drip trough 46 may be employed. It will be understood that the plates C may be tied into the fan system or cycle or, if desired additional cycling means may be provided for the additional plates or evaporators. It may be convenient, in employing my invention, to have the plate sequences B and C in separate series, as indicated diagrammatically in Fig. 8.

With reference to Figure 4, I illustrate an end plate or evaporator D with its supporting brackets 47 and its drip trough 48. It will thus be understood that I may arrange my cooling elements, such as vacuum plates at any desired point or area of the inner surfaces which bound the storage space within the car. However, in general it is suliicient, and advantageous, to mount the plates or evaporators on or along the roof, where they are out of the way, are not damaged by the loading and unloading of the car, and dont use up valuable space.

In the use of my cooling system, I nd it desirable to employ a suitable time control. I illustrate herein what I may call a traveling container, which is shown as a freight car but which might be a truck ora room on a steamer. This traveling container has an insulated interior storage space, in the present example bounded by the insulated walls, roof and floor of a refrigerated flat car. This space I cool by plates or evaporators through which a volatile refrigerant may be cycled. The particular plates I illustrate herein are what I call vacuum plates, in which the evaporator coil 28 is largely surrounded by a eutectic. However, these plates or coils are not normally cycled during transportation. For example, in preparation for a railroad run, the eutectic of the plate may be frozen solids between compressor-condenser-receiver assembly which I find advantageous to power by a diesel engine such as the engine I3 of Figure l. The refrigerating effect of thc eutectic is suilicient to maintain the desired temperature for a substantial period. On short runs it may not be necessary to operate the cycling assembly at all, but I prefer to provide one and I show it in Figure 7. The time control, after a predetermined time lapse, may be actuated to start the diesel engine I3, which will then operate the compressor I2 to cycle the refrigerant through the evaporators to restore them to full cooling efficiency by refreezing the eutectic. In Figure 7, I illustrate more or less diagrammatically the necessary controls. For lack of space, because of the scale of the drawing, they are not shown in Figure 1. It will be understood, however, that the system shown in Figure 1 will be used in connection with the control assembly shown in Figure '7.

Referring to Figure '7, which illustrates the control circuit, I3 is a diesel engine to which liquid fuel may be supplied through the duct 5I controlled by the valve 52. The valve 52 may, for example, be controlled by the solenoid diagrammatically illustrated at 53. When the diesel engine I3 is operating, it serves to drive the compressor I2. The diesel I3 may be started by any suitable starter, diagrammatically illustrated at 54, Any suitable generator 55, driven by the diesel engine, may be employed to maintain a charge in the battery 56. 51 generally indicates a thermostat responsive to temperature within the car, It includes the heat responsive warping bar 58 and the normally fixed contacts 59 and 60.

Assume that a loaded car, with properly frozen eutectic charged vacuum plates, begins a trip. For a predetermined period of time no additional refrigeration is necessary, since the frozen eutectic maintains the interior of the car at the desired temperature. With reference to Figure 7, I may rely on a time device for initiating the cycling of the volatile refrigerant after a predetermined period, by starting the diesel engine I3 to recharge the plates by freezing the eutectic. For example, I illustrate any suitable clock 6I, with its associated time switch 62, having the moving contact 63 and plurality of fixed contacts 64. Assume that it is desired to start the engine when the moving contact 63 reaches the xed contact 64a. A suitable conductor is connected to the contact 64a and extends thence, as at 65, to the starter 54. 66 is any suitable vacuum control switch responsive to the pressure of the diesel.

It will be understood that as soon as the engine starts, the switch 66 is operative to prevent further current flow through the conductor 65.

Ihe starting circuit is completed by the conl ductor 6l, in which the battery 56 is included. 68 is any suitable switch for actually breaking the starting circuit. Thus it will be understood that when the movable contact 63 reaches the fixed contact to which the conductor 65 extends, for example, the contact 64a, the starter 54 is battery-driven to start the diesel I3. As soon as the diesel I3 starts, the pressure condition in the engine opens the switch 66 and prevents further flow of current through the starting circuit. 9

Thus cycling of the volatile refrigerant through the plates is initiated after a predetermined time lag, which can be varied or controlled at the desire of the operator, through the clock 6I and the adjustable time switch 62.

If I wish, I can arrange to stop the operation of the diesel, and thus the cycling of the volatile refrigerant, after a further predetermined and controllable time lag. I may employ a stopping circuit including the conductor 'I0 which may,

for example, be connected to the xed contact 64b. The conductor l0 extends to the conductor 61, as at 10a, and forms a stopping circuit in which the solenoid 53 and the battery 56 are included. Thus, when the movable contact 63 reaches the fixed contact 64b, and assuming that the switch 'mb is closed, the solenoid valve 53 is energized to close the valve 52, and to prevent, for the time being, any further ow of fuel along the pipe 5I to the diesel I3. It will be understood, of course, that as soon as the contact 63 passes the contact 64b, the solenoid is deenergized and the valve 52 is open, so that it will not prevent later starting of the diesel engine. It will also be understood that as soon as the diesel stops, the switch 66 is closed, ready for the next starting impulse. It will be understood, `of course, that any suitable means may be employed for varying the setting of the time switch so that, at the will of the operator, the diesel can be started after a predetermined time lag, and may again be stopped after a predetermined time of operation. Both the starting and the stopping circuits may also be put out of action by opening the manual switches 58 or 18h, respectively.

In place of, or as a supplement to, the time control I may employ a thermostatic control responsive to the temperature within the storage space. Assume that within a predetermined temperature range, the warping member 58 remains in the intermediate position in which it is shown in Figure 7. As long as it is in that position the thermostat has no control over the operation of the cycling system. After a predetermined temperature increase the warping bar 58 moves to the right to contact the xed contact 60. When it does so, current lows from the battery 56 through the conductor '15, and at that time closed switch 16, through the Warping bar 58, the fixed contact 60, the switch 11, the conductor 18, and back through the con ductor 65 and the vacuum controlled switch 66 to the starter 54. The result is the starting of the diesel I3, in response to the movement of the warping bar 58 against the hot contact 60. If the various switches are set to close the thermostatic circuits and to open the time control circuits, then the diesel will continue to operate until the warping bar 58 moves to the left, away from the hot contact 60 and against the cold contact 59. The contact of the warping bar 58 with the cold contact 59 closes a stopping circuit through the conductor 86 to the solenoid 53 and back along the conductor 'I0 to the battery 56 and back across the switch 'I6 to the warping bar 58.

Thus I show a time controlled starting circuit, a thermostat controlled starting circuit, a time controlled stopping circuit, and a thermostat controlled stopping circuit. By merely closing the proper switches I can obtain the following operative features:

f A) I may start the engine and stop the engine, both by time control only.

(B) I may stop the engine and start the engine, solely by thermostatic control.

(C) I may start the engine by time control and stop the engine by thermostatic control.

I thus provide a very flexible operating system in which, by the mere manipulation of switches, the operator may determine whether he will rely solely on time control, solely on thermostatic control, or on a combination of time and thermostatic control. This is very helpful in connection with the different lengths of trip or run which maybe made by a given refrigerating car, and, also, it permits the operator to relate his control system to the ambient temperatures or changes in temperature to which the exterior of the car or truck is subjected.

As a further simpliiication, it will be understood that if al1 the switches are open except the starting switch, the engine can be started and permitted to run continuously until the end of the trip. This may be important, as where a low temperature is desired and goods are being handled which would not be handled by a higher temperature.

With reference to Figure 8, I illustrate the arrangement whereby a multiple of eutectic filled plates, indicated as the series B and the series C may be so connected to the cycling system as to be alternatively put in use or kept out of use. For example, the operator may wish to have all of the plates simultaneously functioning, or he may wish to cut out some of the plates.' In Figure 8, I illustrate a single expansion valve I9 which receives a volatile refrigerant under pressure along the duct I8, and delivers it by the duct |83 to the bank B, and by the duct 104 to the bank C. The two banks then return the evaporated refrigerant along the return duct I4 to the compressor. In order to cut the bank C in or out, as desired, I may, for example, employ any suitable thermostat H16 with its xed contacts I'l, |98, and its temperature responsive contact |88 in circuit with any suitable power source, such as the battery I I0. I I I generally indicates a solenoid controlled valve, therebeing two solenoid windings H2 and I I3 respectively. When the warping contact |09 contacts the fixed contact |08, a circuit is closed through the solenoid winding I I2 and the closed switch I Id. The energization of the winding iIZ actuates the valve, which may be set either to open or to close, depending upon the desire of the operator. At the same time, the switch II4 is opened to prevent drain on the battery III). Assume that the winding III is effective to open the valve, and that the bank B is active. After a predetermined period, the warping bar |09 swings into contact with |01 and energizes the Winding II3. The result is to close the valve, cutting out the bank B. At the same time, the switch IIS is opened, preventing drain on the battery Ill.

Thus I illustrate a system whereby, of the total number of plates within the car or storage space, I may selectively cut Some out, while leaving others connected in the cycling system. Figure 8 illustrates a circuit whereby this can be done thermostatically, but I do not wish to be so limited, as I may manually out out some of the plates, if desired.

It will be understood that whereas I illustrate in Figure 8 the plate series B and C as forming individual controllable series, any other suitable arrangement or subdivision may be employed, whereby individual plates or groups of plates can be rendered inoperative in response to changes in temperature conditions.

The use and operation of the invention are as follows:

The structure herein described and shown provides, in various forms, a refrigerating or refrigerated container such as a car or truck body. The container, with its insulated walls, such as I, 2, 3, 4 and 5, houses or surrounds a space in which material may be stored and transported in frozen condition. Preferably, the plates are, as shown in Figure 6, partially or substantially lled by an eutectic solution which is frozen solid before the car or container starts its run. If the material to 'be stored and transported in the container needs any precooling, then the frozen eutectic will absorb the extra heat from the goods transported, without raising the temperature of the storage space or of the containerwalls. For example, if the material is to be stored and transported at, say F., and if it is put into the container or car at a temperature above 0, the eutectic is available to absorb the excess heat of the material transported and to bring it down to the desired temperature of, for example, `0" F. Thus material may be placed in the storage zone within the car, and be precooled there before or at the beginning of the transportation trip. It will make the trip, and end the trip, within a substantial time range, at its O temperature, there being no increase in the sensitive heat in the interior of the car or in the goods transported.

It will be understood that when the eutectic is completely frozen, the system again ceases to cycle. For this reason, I may employ a suitable thermostatic control responsive to the drop in temperature of the eutectic.

I may also employ, as a supplementary control, a temperature responsive assembly for initiating operation of the motor in response to a predetermined temperature rise.

It will ,be understood that I do not limit my invention to the use of a diesel engine, although a diesel engine is an eicient motor means for use in freight cars, refrigerated trucks and the like.

It will be realized that, whereas, I have clescribed and illustrated a practical and operative device, nevertheless many changes may be made in the size, shape, number and disposition of parts without departing from the spirit of my invention. I therefore wish my description and drawings to be taken as in a broad sense illustrative or diagrammatic, rather than as limiting me to my precise showing.

I claim:

l. In combination with an insulated container defining a storage space, a plurality of evaporator plates, each plate including generally parallel, plane side walls sealed about their edges to form an hermetically closed space, with a coil in each said plate in heat transfer relationship with the inner surfacesv of the side walls of the plates, the space within the plates and about the coils being partially filled by an eutectic, the plates being arranged in a plurality of groups, a compressor for cycling a volatile refrigerant through said plates, and connecting ducts between said compressor and the plates, all the plates normally operating at substantially the same temperature, a common supply pipe for the groups of plates, extending from the delivery side of the compressor, branch supply pipes extending from the common supply pipe to the groups, a valve in one such branch supply pipe, a thermally responsive member subjected to temperature changes in said storage space, and an actuating connection between said thermally responsive member and valve, adapted to close said valve in response to a predetermined temperature drop in said storage space.

2. The structure of claim 1 characterized in that the plates in the individual groups are arranged in series, each series being connected to one of the branch supply pipes.

3. The structure of claim 1 characterized by and including a single expansion element, common to the branch supply pipes, located between the groups of plates and the compressor.

4. The structure of claim 1 characterized by and including a single expansion element between the compressor and the groups of plates, a valve connection 4between said expansion element and one such group of plates, and means responsive to temperature conditions within the container for actuating said valve connection.

5. The structure of claim 1 characterized in that the groups are arranged in parallel, the plates in the individual groups being arranged in series.

6. In combination with an insulating container defining a storage space, a plurality o evaporator plates, each plate including sido walls sealed about their edges to form an hermetically closed space, with a coil at each said plate in heat transfer relationship with the inner surfaces of the side walls of the plates, the space within the plates and about the coils being partially filled by an eutectic, the plates being arranged in a plurality of independent groups, a compressor for cycling a volatile refrigerant through said groups and through the individual plates of said groups, connecting ducts between said compressor and groups, and all the plates normally operating at substantially the same temperature, a common supply pipe for the groups of plates, extending from the delivery side of the compressor, branch supply pipes extending from the common supply pipe to the groups, a Valve in one such branch supply pipe, a thermally responsive member subjected to temperature changes in said storage space, and an actuating connection between said thermally responsive member and valve, adapted to close said valve in response to a predetermined temperature drop in said Storage space.

7. In a vehicle and in combination with an insulated container of such vehicle defining a storage space, a plurality of evaporator plates, each plate including side walls sealed together to form an hermetically closed space, with the coil in each side plate in heat transfer relationship with the walls of the plate, the space within the plates and about the coil being at least partially filled by an eutectic, the plates being arranged in a plurality of groups, a compressor for cycling a Volatile refrigerant through said plates, and connecting ducts between said compressor and the plates, all plates normally operating at substantially the same temperature, a common supply pipe or the groups of plates, extending from the delivery side of the compressor, branch supply pipes extending from the common supply pipe to the groups, pressure reduction means between said common supply pipe and the branch pipes, adapted to control the pressure to both groups of plates, and a valve in one such branch supply pipe and an actuating connection for said valve, adapted to close said valve and to eliminate one such group of plates from the cycling system while permitting refrigerant to cycle through another such group.

8. In a vehicle and in combination with an insulated container of such vehicle dening a storage space, a plurality of evaporator plates, each plate including side walls sealed together toform an hermetically closed space, with the coil in each side plate in heat transfer relationship with the walls of the plate, the space within the plates and about the coil being at least partially lled by an eutectc, the plates being arranged in a plurality of groups. a compressor for cycling a volatile refrigerant through said plates, and connecting ducts between said compressor and the plates, all plates normally operating at substantially the same temperature, a common supply pipe for the groups of plates, extending from the delivery side of the compressor, branch supply pipes extending from the common supply pipe to the groups, pressure reduction means between said common supply pipe and the branch pipes, adapted to control the pressure to both groups of plates, a valve in one such branch supply pipe, and a member adapted toclose said Valve upon a predetermined temperature drop in such storage space and to eliminate one such group of plates from the cycling system while permitting a refrigerant to cycle through another such group.

HERMAN W. KLEIST.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,102,725 Lithgow Dec. 21, 1937 2,134,107 Dempsey Oct. 25, 1938 2,286,538 Guler June 16, 1942 2,435,107 Sutton Jan. 27, 1948 2,455,850 Atchisson Dec. 7, 1948 2,479,128 Maniscalco Aug. 16, 1949 2,534,272 Kleist Dec. 19, 1950 OTHER REFERENCES Fedders News, Jan. 1940, vol. 7, No. 1, pp. 3 and 4, published by Fedders Manufacturing Company, Buialo, New York. 

